The present invention relates to a combustion-type power tool, and more particularly, to such power tool capable of driving a fastener of driving such as a nail, an anchor, and a staple into a workpiece by igniting a mixture of air and gaseous fuel, which in turn causes a linear momentum of a piston.
U.S Pat. Nos. 4,483,474, 4,403,722, 4,522,162, 4,483,473, and 5,191,209 disclose a combustion type power tool in which motive power of a piston is generated upon ignition of air-fuel mixture to drive a fastener such as a nail and a rivet into a workpiece.
The power tool generally includes a housing frame, a head cover, a combustion chamber frame, a cylinder, a piston, a driver and blade. The head cover is positioned at one end of the housing frame. The combustion chamber frame is reciprocally movable and abuttable on the head cover. The cylinder is disposed in the housing frame. The piston is reciprocally movable within the cylinder. The driver blade is attached to the piston to drive the fastener by the movement of the piston. A sealed combustion chamber is defined by the head cover, combustion chamber frame, cylinder, and piston when the combustion chamber frame is in abutment with the head cover. A gas canister accumulating therein a combustible fuel is provided in the housing frame. An ignition plug is provided to generate a spark for igniting air-fuel mixture when the fuel is injected and vaporized in the combustion chamber. Upon explosive combustion, the piston is rapidly moved to move the driver blade so that the fastener is driven into the workpiece.